Industrial Robot – Upper and Lower Arms

The upper and lower arms of industrial robots are core structural castings for the motion and load-bearing functions of the complete machine and directly affect equipment running accuracy, repeat positioning accuracy, and overall stability. As the domestic industrial robot industry develops rapidly, the industry imposes increasingly stringent requirements on the contour flatness, dimensional tolerances, and surface consistency of arm castings. Traditional manual grinding suffers from poor precision and large batch fluctuations and can hardly meet the mass-production supporting standards of high-end robots.

Robot upper and lower arms are mostly produced through precision sand casting, featuring numerous hollowed-out structures, complex curved surfaces, and uneven wall thickness distribution. During the casting cooling and forming process, irregular shrinkage and expansion deformation is highly prone to occur, with noticeable differences in deformation between individual castings. Fine flashes, burrs, and oxide scale tend to form on parting surfaces, mounting hole positions, and curved surface edges. Traditional fixed fixtures are positioned according to theoretical dimensions and cannot accommodate casting deformation deviations, making quality problems such as hole position grinding deviation, under-grinding of curved surfaces, and localized over-grinding highly prone to occur.

To address the grinding pain points of precision robot arm castings, Quanyu Industry has developed a dedicated automated grinding solution based on its core 3D vision deviation correction technology. The equipment scans and captures the actual contour of each arm casting in real time, uses self-developed algorithms to precisely calculate casting shrinkage and expansion deformation and automatically compensate for it, and dynamically generates a grinding trajectory adapted to each individual workpiece. It precisely removes burrs from complex curved surfaces, hole positions, and edges and corners, effectively resolving the industry challenges of inaccurate positioning and poor grinding precision for deformed castings.

After the equipment was put into application, the customer's robot arm casting grinding precision and batch consistency improved significantly, and the defect rework rate dropped markedly. Automated grinding replaces manual fine grinding processes, effectively improving capacity and efficiency and reducing labor costs and quality risks. It stably meets the assembly standards of high-end industrial robots, helping the enterprise enhance its core supporting competitiveness and achieve quality improvement, efficiency enhancement, and cost reduction.

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